Getting email bounce back after successfully creating Outlook event

Hi Graph Team,

I have managed to get a success response when calling the Graph API Outlook event endpoint, however the email that is generated bounces back with the following error:

Diagnostic information for administrators:

Generating server: DB9PR06MB7322.eurprd06.prod.outlook.com

email address removed for privacy reasons
Remote server returned '550 5.7.501 Service unavailable. Spam abuse detected from IP range. For more information please go to http://go.microsoft.com/fwlink/?LinkId=526653

Original message headers:

Received: from DB9PR06MB7322.eurprd06.prod.outlook.com
 ([fe80::bc07:efdc:8de2:cdf9]) by DB9PR06MB7322.eurprd06.prod.outlook.com
 ([fe80::bc07:efdc:8de2:cdf9%4]) with mapi id 15.20.7633.033; Fri, 7 Jun 2024
 15:37:39 +0000
MIME-Version: 1.0
Content-Type: text/plain
Date: Fri, 7 Jun 2024 15:37:39 +0000
Message-ID:
     <email address removed for privacy reasons>
Subject: Test Email

May you kindly assist on the steps I should take to resolve this